This proposal requests a Thermo Finnigan ProteomeX DECAP-51000 Integrated Workstation, an ion trap mass spectrometer equipped with LC pumps, a 10 port switching valve, strong cation and reversed phase columns for multidimensional chromatography, and a nanospray probe. This instrument will serve the needs of a number of University of Arizona bioscience researchers. The major users and their applications for the instrumentation are (1) Samuel Ward, Molecular and Cellular Biology, Study of signaling pathways during cell differentiation in the Nematode C.elegans, genes are homologeous to human disease genes linked to Alzheimer's and muscular dystrophy; (2) Brian Larkins, Plant Sciences, College of Agriculture and Life Sciences, Identificationand Analysis of Proteins Required for Improved Maize Protein Nutritional Quality; (3) M. Halonen/D. Vercelli/F. Martinez/M. Cusanovich, Center for Respiratory Sciences, Transcription Factors that Bind Regulatory Elements in the Immunoglobulin G4 Germline Promoter, the IL-13 Promoter, and the CD 14 Promoter; Cellular and Molecular Mechanisms of Asthma (4) Elizabeth Vierling, Molecular and Cellular Biology, Molecular chaperone function; expression and function of cytoplasmic organelle and heat shock proteins, the pathways studied are critical to normal cell function; (5) Carol Dieckmann, Biochemistry, Identification of Mutations in Genes Coding for Major Polypeptides in the Chlamydomonas Eyespot;, (6) Thomas Baldwin, Biochemistry, Pulsed Alkylation MS to Investigate Protein Folding in Bacterial Luciferase; (7) Vicki Wysocki, Chemistry, Mechanisms and Energetics of Peptide Dissociation, this work is directly applicable to the identification of proteins from biological organisms. Modern protein research cannot be accomplished without mass spectrometry. The access to a dedicated microflow LC-mass spectrometer with a nanospray probe to characterize samples that are not amenable to analysis with the current mass spectrometry facility instruments is critical to the maximum productivity and success of these projects. The University has made a strong commitment to the project by by renovating space for a new "branch" mass spectrometry laboratory that is located in Biosciences, by hiring a full time Ph.D. biological mass spectrometry specialist (about $60,000 per year), by providing funds for a Director of Proteomics (about $80,000/year) and a technician (about $35,000/year) to help with sample preparation, and by providing cost sharing in the amount of $75,000.